The Script Module has the same API as the `wp-a11y` WP Script.
Key changes:
- Add `@wordpress/a11y` to the list of Script and Module dual packages.
- Update `script-modules-packages.min.php` to include the a11y module.
- Modify `WP_Script_Modules` class to track and handle a11y module availability.
- Add method to print required HTML markup for a11y `speak()` functionality.
See #60647.
Props jonsurrell, gziolo, czapla.
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czapla